On 12/12/11 02:42, Malcolm Wallace wrote:
The extra parameter "i" is for "information" attached to each node of
the tree. As you have correctly guessed, the parser fills in this
field with positional information relating to the original source
document, which is useful for instance if you are validating or
checking the original document. When building new parts of a
document, it is perfectly fine to attach "noPos".
You can alternatively replace all of the informational items in the
tree, with for instance "fmap (const ())" if you don't care about
them.
The information fields are useful for other purposes though, e.g. to
hold the relevant xmlns namespace for subtrees; or to distinguish
added/removed/modified subtrees in a diff-like viewer.
Regards, Malcolm
Thanks, I understand what's going on now.
I like the noPos solution because the other ones make the reader think
there's something important going on; with noPos, I can just comment
"gotta give it a Posn, and this is the only one I know how to make."
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